<template>
  <div>
    <!-- 评论列表 -->
    <div class="cmt-list" :class="isShowCmtInput ? 'art-cmt-container-2' : 'art-cmt-container-1'">
      <!-- 评论的 Item 项 -->
      <van-list
        v-model="loading"
        :finished="finished"
        finished-text="没有更多了"
        @load="onLoad"
        offset="50"
        :immediate-check="false"
      >
      <div class="cmt-item" v-for="comment in commentList" :key="comment.com_id" >
        <!-- 头部区域 -->
        <div class="cmt-header">
          <!-- 头部左侧 -->
          <div class="cmt-header-left">
            <img :src="comment.aut_photo" alt="用户头像" class="avatar">
            <span class="uname">{{comment.aut_name}}</span>
          </div>
          <!-- 头部右侧 -->
          <div class="cmt-header-right">
            <van-icon name="like" size="16" color="red" v-if="comment.is_liking === true" @click="likingComment(comment, false)"/>
            <van-icon name="like-o" size="16" color="gray" v-else  @click="likingComment(comment, true)"/>
          </div>
        </div>
        <!-- 主体区域 -->
        <div class="cmt-body">
          {{comment.content}}
        </div>
        <!-- 尾部区域 -->
        <div class="cmt-footer">{{formatTime(comment.pubdate)}}</div>
      </div>
      </van-list>
    </div>

    <!-- 底部添加评论区域 - 1 -->
    <div class="add-cmt-box van-hairline--top" v-if="!isShowCmtInput">
        <van-icon name="arrow-left" size="0.48rem" @click="$router.back()" />
        <div class="ipt-cmt-div" @click="isShowCmtInput = true">发表评论</div>
        <div class="icon-box">
            <van-badge :content="commentTotal" max="99" @click.native="moveComment">
                <van-icon name="comment-o" size="0.53333334rem" />
            </van-badge>
            <van-icon name="star-o" size="0.53333334rem" />
            <van-icon name="share-o" size="0.53333334rem" />
        </div>
    </div>

    <!-- 底部添加评论区域 - 2 -->
    <div class="cmt-box van-hairline--top" v-else>
      <!-- 自动获得焦点，失去焦点时关闭发表评论显示 -->
        <textarea placeholder="友善评论、理性发言、阳光心灵"
        v-model.lazy="content"
        v-myfocus
        @blur="closeCommentInput"
        ></textarea>
        <van-button type="default" :disabled="content.length===0" @click="commitComment" ref="commentButton">发布</van-button>
    </div>
  </div>
</template>

<script>
import { commentListAPI, commentLikingAPI, commentDisLikingAPI, sendCommentAPI } from '@/api/index'
import { timeAgo } from '@/utils/date'
export default {
  name: 'CommentList',
  data () {
    return {
      commentList: [], // 评论数据
      offset: '', // 偏移量 评论id
      isShowCmtInput: false,
      content: '', // 评论内容
      commentTotal: '', // 评论数
      finished: false, // 加载是否完成
      loading: false // 加载状态
    }
  },
  methods: {
    formatTime: timeAgo,

    // 获取评论列表
    async getCommentList () {
      const res = await commentListAPI({
        id: this.$route.query.aid,
        offset: this.offset
      })
      if (res.data.data.results.length === 0) {
        this.finished = true
      }
      // 合并评论数组
      this.commentList = [...this.commentList, ...res.data.data.results]
      this.commentTotal = res.data.data.total_count || '' // 空字符串,防止出现徽标0
      this.offset = res.data.data.last_id // 最后一个id，偏移量
      this.loading = false
    },
    // 点赞评论
    async likingComment (comment, bool) {
      // 点赞
      if (bool) {
        comment.is_liking = true
        commentLikingAPI({
          comId: comment.com_id
        })
      } else {
        // 取消点赞
        comment.is_liking = false
        commentDisLikingAPI({
          comId: comment.com_id
        })
      }
    },
    // 跳转到评论区
    moveComment () {
      this.$bus.$emit('move')
    },
    // 失去焦点时关闭评论输入区
    closeCommentInput () {
      setTimeout(() => {
        this.isShowCmtInput = false
      }, 300)
    },
    // 发布评论
    async commitComment () {
      const res = await sendCommentAPI({
        aid: this.$route.query.aid,
        content: this.content
      })

      // 保存到评论数组
      this.commentList.unshift(res.data.data.new_obj)
      // 评论数+1
      this.commentTotal++
      // 清空评论区
      this.content = ''
      // 跳转到刚发布的评论
      this.moveComment()
    },
    async onLoad () {
      if (this.commentList.length > 0) {
        this.getCommentList()
      } else {
        this.loading = false
      }
    }
  },
  async created () {
    this.getCommentList()
  }
}
</script>

<style scoped lang="less">
.cmt-list {
  padding: 10px;
  .cmt-item {
    padding: 15px 0;
    + .cmt-item {
      border-top: 1px solid #f8f8f8;
    }
    .cmt-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      .cmt-header-left {
        display: flex;
        align-items: center;
        .avatar {
          width: 40px;
          height: 40px;
          background-color: #f8f8f8;
          border-radius: 50%;
          margin-right: 15px;
        }
        .uname {
          font-size: 12px;
        }
      }
    }
    .cmt-body {
      font-size: 14px;
      line-height: 28px;
      text-indent: 2em;
      margin-top: 6px;
      word-break: break-all;
    }
    .cmt-footer {
      font-size: 12px;
      color: gray;
      margin-top: 10px;
    }
  }
}

/*美化 - 文章详情 - 底部的评论页面 */
// 外层容器
.art-cmt-container-1 {
  padding-bottom: 46px;
}
.art-cmt-container-2 {
  padding-bottom: 80px;
}

// 发布评论的盒子 - 1
.add-cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  box-sizing: border-box;
  background-color: white;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 46px;
  line-height: 46px;
  padding-left: 10px;
  .ipt-cmt-div {
    flex: 1;
    border: 1px solid #efefef;
    border-radius: 15px;
    height: 30px;
    font-size: 12px;
    line-height: 30px;
    padding-left: 15px;
    margin-left: 10px;
    background-color: #f8f8f8;
  }
  .icon-box {
    width: 40%;
    display: flex;
    justify-content: space-evenly;
    line-height: 0;
  }
}

.child {
  width: 20px;
  height: 20px;
  background: #f2f3f5;
}

// 发布评论的盒子 - 2
.cmt-box {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 80px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-left: 10px;
  box-sizing: border-box;
  background-color: white;
  textarea {
    flex: 1;
    height: 66%;
    border: 1px solid #efefef;
    background-color: #f8f8f8;
    resize: none;
    border-radius: 6px;
    padding: 5px;
  }
  .van-button {
    height: 100%;
    border: none;
  }
}
</style>
